Patterns of Hearing Loss Presentations in Maitama District Hospitals Abuja-Nigeria
Challenges in Management.
By: Dr M Ahmed-Danfullani (Consultant ENT surgeon)
Mr Audu Eneche (Audiologist)
Introduction
Burden of hearing loss on individuals and society at large is enormous, the impact of these on any economy is therefore significant. The role of adequate hearing in day to day life can not be overemphasized, attainment of millennium development goals viz; education and eradication of poverty are strictly tied to adequate hearing and therefore not achievable unless issues of hearing impairment are addressed especially in children[1].
The cost of treating hearing impairment is still very high even in developed society[1], in resource limited environment such as ours, access to qualitative health, identification of hearing problems and availability of treatment are still a mirage even in the big cities[2]. Therefore primary prevention of deafness through awareness campaign at the primary care level is still the best options [1, 2].
Methodology
All patients who attend our clinic over a period of one year (Between Jan –Dec 2006) with history of hearing loss were recruited.
Physical examinations and basic hearing assessment (PTA,Tympanometry, and, occasionally oto acoustic emissions and ABR were done when patient can afford.
Results were analyzed and presented in both data and graphical forms.
(see tables and Figures).
Results
A total of 1065 patients were seen over the period under consideration.(table 1).
M/F ratio is 1:1 mix hearing loss accounted for about (38%) of all the cases seen followed by conductive deafness alone mostly due to wax impaction and chronic supurative otitis media (27.7%).
Pure Sensorineural Hearing loss were seen in about(23% )of the patients(table 2), mostly due to congenital malformations, birth asphyxia, familial and idiopathic causes.(11%) of these have severe to profound deafness (8% ) prelingual (3%) post lingual.
The commonest type of deafness amongst children in our experience is mixed hearing loss mostly due to OME ,congenital malformations, CSOM, and idiopathic causes.(13%) of these were pre lingual and had severe to profound Deafness[1,2,6 ].
Amongst post lingual children and adults, previously healed CSOM., ototoxicity were the leading causes[2].
Meningitis as a cause of deafness in our environment is on the decrease.
Sudden hearing loss was seen in (3%) of the cases[3,4,5].
Myringotomy with or without ventilation tube was excellent for many of the patients especially the pre lingual children [6,7,9]. Hearing aids fitting have been useful in carefully selected patients.
Tables/Figures
Table 1
Female / Male / % / TotalOME / 112 / 88 / 18.8 / 200
Wax impaction / 102 / 123 / 21.1 / 225
CSOM / 191 / 103 / 22.7 / 294
Cong Malformation / 60 / 63 / 11.5 / 123
Ototoxicity / 20 / 18 / 3.6 / 38
Meningitis / 11 / 2 / 1.2 / 13
NIHL / 18 / 90 / 10.1 / 108
Others / 40 / 24 / 6 / 64
Total / 554 / 511 / 100 / 1065
Table 2
Types of Hearing Loss
no / %SNHL / 245 / 23
CHL / 415 / 39
MIXED / 405 / 38
TOTAL / 1065 / 100
Table 3
TYPES OF TREATMENT
Aural Syringing / Myringotomy with Ventilation tube / Hearing aid / Referred315 / 110EARS / 33 EARS / 68
Figure 1
Figure 2
Discussions
The burden of hearing impairment in ORL practice is significant [1], awareness on the importance of hearing conservation is increasing, more and more people now seek for help unlike in the past. In our study the total of 1065 patients represent all types of hearing loss in all age groups and from all causes (table 1). There is no significant sex differences, children less than 18yrs constituted about 65% of the study population (figure 1).
Generally mode of presentations are usually late except in cases of sudden hearing loss in adults[3], this is because a lot of people in our environment belief nothing could be done for hearing loss and will rather try traditional medication and if it fails they then come to the hospital, this is a big challenge in the management of these cases. majority of our patients had mix hearing loss from combination of causes, those with pure conductive deafness are usually sudden, mild to moderate hearing loss and due largely to wax impaction( table 1), OME in children and in HIV positive adults .a case of sudden sensorineural hearing loss was seen in 16yr old sickler.
Chronic supurative otitis media is still a problem in our society, the presentation is still usually late and hardly do they come back for follow up. Although the incidence of acute mastoiditis is decreasing, the sequel of CSOM is responsible for about (27.7%) of the patients seen[2,3,4].
Sensorineural deafness is the most difficult to manage of the presentations, partly because of the aetiology and to the fact that SNHL requires more than just hearing Aid to manage [5]. notable among the causes in our study is the progressive increase in the incidence of noise induced hearing loss and ototoxicity, mostly due to anti-malaria and The aminoglycosides antibiotics. other causes are congenital malformations birth asphyxia with cerebral palsy, familial and idiopathic causes these groups come with a more severe forms of hearing losses and are usually difficult to manage especially when they present post lingual [5,7,9].
Meningitis as a cause of deafness in our study is decreasing this is because meningitis itself is decreasing in incidence because of improved lifestyle and availability of meningitis vaccine [2, 5]; however this has been a great challenge in the past. Idiopathic and bizarre presentations are not uncommon (9%) while more and more cases of familial/genetic cases are coming to the fore(5%), this makes the need for introduction of genetic counseling more imperative in our society.
Investigations of hearing loss in our study is a very difficult one, apart from basic bedside clinical examination and tuning fork tests, others like Pure Tone Audiometry, ABR Tympanometry are all luxury. firstly there are less than two centers for a population of over a million where this facility are available, less than five well trained audiologists in the country, therefore only about 8 patients could afford a complete hearing assessment as this entail traveling several kilometers before this tests can be done, however special arrangements was made for PTA and Tympanometry for all our patients.
If investigating our patients was difficult then certainly managing them was more difficult, except for simple cases of wax impaction for which aural syringing were done, other treatments are a bit challenging. Most cases of severe sensorineural deafness are assessed for hearing aid fitting (33 ears), affordability and maintenance of the AID is a major issue here(see table 3).
Managing OME is a bit tasking, having to use a loop, and most time under LA, however the outcome has been rewarding,(80%) immediate improvement, less than (10%) extrusion rate in 3months, (5.7%) persistent perforation after 6 months and restoration of normal hearing in about (89% )of cases, the procedure was abandoned in (3.2%) of the patients[9].
The authors experience In middle/mastoid ear surgeries is limited and as such much progress was not made especially in the management of CSOM.
Conclusion /Challenges
Man hour loss costs on patient, severe emotional and social deprivation are major issues to the patients. Inadequate facilities, and lack of well trained manpower are some of the challenges faced. Middle ear reconstructions and cochlear implants are expensive and not available to our patients, acquisition of hearing aids and its maintenance is still a challenge. However effective utilization of the meager resources and careful selection of patients has been rewarding
References
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J .Speech Lang.Hear.Res.41(1998)S61-S84.
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8. Joint committee on infant hearing year 2000 position statement :principles and guideline for early hearing detection and intervention programs, int J of paediatrics 106 (2000)798-817.
9.Somefun A. O, Adefuye S A, Danfulani M A, Afolabi S . Adult Onset Otitis Media with effusion Lagos. Nig postgraduate med j 2005 June; 12(2)73-6